
import java.io.*;

import java.net.*;

import java.applet.Applet;

import java.security.MessageDigest;



public class Server3 {

    public static void main(String args[]) {



        MyDC evalute = new MyDC();



        SDec sDec = new SDec();



        try {

            ServerSocket server = null;

            try {

                server = new ServerSocket(4700);

                //创建一个ServerSocket在端口4700监听客户请求


            } catch (Exception e) {

                System.out.println("can not listen to:" + e);

                //出错，打印出错信息


            }

            Socket socket = null;

            try {

                socket = server.accept();

                //使用accept()阻塞等待客户请求，有客户


                //请求到来则产生一个Socket对象，并继续执行


            } catch (Exception e) {

                System.out.println("Error." + e);

                //出错，打印出错信息


            }



            String line;



            BufferedReader is = new BufferedReader(new InputStreamReader(socket.getInputStream()));

            //由Socket对象得到输入流，并构造相应的BufferedReader对象


            PrintWriter os = new PrintWriter(socket.getOutputStream());

            //由Socket对象得到输出流，并构造PrintWriter对象


            BufferedReader sin = new BufferedReader(new InputStreamReader(System.in));

            //由系统标准输入设备构造BufferedReader对象
            //使用Hash函数检测明文完整性


            String x = sin.readLine();



            MessageDigest m2 = MessageDigest.getInstance("MD5");

            //使用MD5算法返回实现指定摘要算法的 MessageDigest对象


            m2.update(x.getBytes());

            byte a[] = m2.digest();

            String result = "";

            for (int i = 0; i < a.length; i++) {

                result += Integer.toHexString((0x000000ff & a[i]) | 0xffffff00).substring(6);

            }

            System.out.println(result);



            String match = is.readLine();

            if (match.equals(result)) {

                System.out.println("匹配成功");

            }



            System.out.println("Client:" + is.readLine());

            //在标准输出上打印从客户端读入的字符串




            line = sin.readLine();

            //从标准输入读入一字符串




            while (!line.equals("bye")) {

                //如果该字符串为 "bye"，则停止循环




                os.println(evalute.evaluate(line));

                //向客户端输出该字符串


                os.flush();

                //刷新输出流，使Client马上收到该字符串




                System.out.println("Server:" + evalute.evaluate(line));

                //在系统标准输出上打印读入的字符串




                System.out.println("Client:" + is.readLine());

                //从Client读入一字符串，并打印到标准输出上


                line = sin.readLine();





                //从系统标准输入读入一字符串


            }  //继续循环


            os.close(); //关闭Socket输出流


            is.close(); //关闭Socket输入流


            socket.close(); //关闭Socket


            server.close(); //关闭ServerSocket


        } catch (Exception e) {

            System.out.println("Error:" + e);

//出错，打印出错信息


        }

    }

}